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A relational database developer refers to a record as:
Answer: A tuple.
In an E-R diagram attributes are represented by:
Answer: Ellipse
DBMS helps achieve:
Answer: Both (A) and (B).
In an E-R diagram double lines indicate
Answer: Total participation.
The DBMS acts as an interface between what two components of an enterprise-class database system?
Answer: Database application and the database
Which of the following is an accurate statement in regard to an E-R diagram?
Answer: It creates an abstraction of information handled in operations, so as to express entities and the relations between them.
A set of possible data values is called:
Answer: Domain
A table can have only one
Answer: Primary key
The file organization that provides very fast access to any arbitrary record of a file is:
Answer: Hashed file.
A relation is considered a:
Answer: two-dimensional table.
In a relation
Answer: both
The conceptual model is:
Answer: Independent of both hardware and software
Answer:
You are building a new database for a company with 10 departments. Each department contains
multiple employees. In addition, each employee might work for several departments. How
should you logically model the relationship between the department entity and the employee
entity?
Answer: Create a new entry, create a one-to-many relationship from the employee to the new
entry, and create a one-to-many relationship from the department entry to the new entry.
Which of the following is another name for weak entity?
Answer: Child
In case of entity integrity, the primary key may be:
Answer: Not Null
Answer:
Which of the following is the appropriate characteristic of a database?
Answer:It can be accessed by multiple users at the same time due to an exclusive control
function.
Which option is not TRUE?
Answer: Neither (A) nor (B)
Which of the following is described graphically using an E-R diagram?
Answer: Entities and relationships between entities
An instance of relational schema R (A, B, C) has distinct values of A including NULL values. Which one of the following is true?
Answer: A is not a candidate key
Consider the join of a relation R with relation S. If R has m tuples and S has n tuples, then the maximum size of join is:
Answer: mn
When the data model is represented to conform to the notational convention shown below,
which of the following statements appropriately interprets the designated E-R diagram?
Answer: It does not occur that a single order placement is given to multiple suppliers.
What is data integrity?
Answer: It is the data contained in database that is accurate and consistent.
The entity-relationship diagrams A and B shows the relationships between three entities in a school:
teacher, class, and classroom. Which of the following is an appropriate interpretation concerning the
diagrams? Here, " 1 1 " shows a one-to-one relationship while " 1 * " shows a one-to-many relationship.
Answer: In A, a teacher is responsible for one class only. In B, a teacher may
be responsible for one or more classes
An advantage of the database management approach is:
Answer: Data is integrated and can be accessed by multiple programs.
It is better to use files than a DBMS when there are:
Answer: Multiple users wish to access the data.
NULL is:
Answer: Not a value
Answer: 1:1
Which of the following are the properties of entities?
Answer: Attributes
You are tasked with creating a database to manage where computers are installed at a company that has
offices in several buildings. You create an “asset” table, a “room” table, and a “building” table, and link
each of them together. When new data is entered, the data in the referenced table must already exist.
Which of the following is the appropriate order of in-put? Here, the underlined items in each table are
either primary or foreign keys.
Answer: “Building” table →“Room” table →“Asset” table
In the ERD diagram, the one-to-many relationship, "a company has multiple employees," is expressed as
follows:
Answer: There are multiple companies, and each company has multiple shareholders.
If the condition given below applies, which of the following is appropriate as an E-R diagram showing the
departments employees belong to?
Answer: Emp<-Dep
The values of the attribute describes a particular _____
Answer: Entity instance
In the relational modes, cardinality is termed as:
Answer: Number of tuples.
What is a relationship called when it is maintained between two entities?
Answer: Binary
Which of the following appropriately describes a domain (defined area), a term used for relational
databases?
Answer: It is a set of values that attributes can hold.
The database environment has all of the following components except:
Answer: Users
An entity set that does not have sufficient attributes to form a
primary key is a:
Answer: Weak entity set.
The method in which records are physically stored in a specified order according to a key field
in each record
Answer: Hash
Which of the following appropriately describes a schema in a
relational database management system?
Answer: It is a set of data definitions such as the data
properties, format, relationship with other data, etc.
Which of the following is not a restriction for a table to be a
relation?
Answer: The columns must be ordered.
The RDBMS terminology for a row is:
Answer: Tuple
Conceptual design
Answer: Involves modelling independent of the DBMS.
A DBMS query language is designed to:
Answer: All of the above.
Which of the following is expressed by an E-R diagram?
Answer: Relation between entities
In E-R diagram generalization is represented by
Answer: Triangle
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